Resolve markdown links correctly

scm-ui/ui-components/src/MarkdownLinkRenderer.tsx

@@ -0,0 +1,87 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020-present Cloudogu GmbH and Contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+import React, { ReactNode } from "react";
+import { withRouter, RouteComponentProps } from "react-router-dom";
+import { withContextPath } from "./urls";
+
+type Props = RouteComponentProps & {
+  children: ReactNode;
+  href: string;
+};
+
+function flatten(text: string, child: any): any {
+  return typeof child === "string" ? text + child : React.Children.toArray(child.props.children).reduce(flatten, text);
+}
+
+/**
+ * Handle local SCM-Manager and external links
+ *
+ * @VisibleForTesting
+ */
+export function correctLocalLink(pathname: string, link: string) {
+  if (link === "") {
+    return pathname;
+  }
+
+  // Leave uris unchanged which start with schemes
+  const regex = new RegExp(".:");
+  if (link.match(regex)) {
+    return link;
+  }
+
+  // Reference to the main directory possible if link starts with slash
+  let base = "";
+  let path = link;
+  if (!link.startsWith("/")) {
+    base = pathname;
+    // Remove last slash temporary
+    if (base.endsWith("/")) base = base.substring(0, base.length - 1);
+    // Remove current called file from path
+    base = base.substr(0, base.lastIndexOf("/") + 1);
+
+    // Remove first slash for absolute consistence
+    if (path.startsWith("/")) path = path.substring(1);
+  }
+
+  // Link must end with fragment if it contains one
+  const pathParts = path.split("#");
+  if (pathParts.length > 1) {
+    // Add ending slash in front of fragment
+    if (!pathParts[0].endsWith("/")) pathParts[0] += "/";
+    path = pathParts[0] + "#" + pathParts[1];
+  } else {
+    // Add ending slash
+    if (!path.endsWith("/")) path += "/";
+  }
+
+  return base + path;
+}
+function MarkdownLinkRenderer(props: Props) {
+  const compositeUrl = withContextPath(correctLocalLink(props.location.pathname, props.href));
+  const linkText = React.Children.toArray(props.children).reduce(flatten, "");
+
+  return <a href={compositeUrl}>{linkText}</a>;
+}
+
+export default withRouter(MarkdownLinkRenderer);